Panicum amarum Elliott

Panicum amarum Ell. Bot. S. C. & Ga. 1: 121. 1816
Panicum amarum minus Vasey & Scribn.; Vasey, Bull. U. S. Dep. Agr. Bot. 8: 38. 1889. Panicum amaroides Scribn. & Merr.; Scribn. Circ. U. S. Dep. Agr. Agrost. 29: 5. 1901. Chasea amara Nieuwl. Am. Midi. Nat. 2: 64. 1911.
Plants glaucous and glabrous throughout; culms solitary from the nodes of extensively creeping, horizontal rootstocks, simple or occasionally branching from the lower nodes, 30-100 cm. high; leaf-sheaths overlapping but commonly narrow and partially exposing the short, very glaucous internodes; ligule dense and silky, about 3 mm. long; blades ascending or spreading, thick, 10-30 cm. long, 5-12 mm. wide, broadest at the base, flat below, involute toward the tip, the margins smooth; panicles short-exserted or included at base, one fourth to one third the height of the plant, or sometimes more, not more than 3 cm. wide, mostly few-flowered, the distant, appressed branches bearing scattered, short, appressed branchlets with approximate, short-pediceled spikelets; spikelets 5-6.5 mm. long, about 2. mm. wide and as much as 3 mm. thick, narrowly ovate, acuminate, strongly nerved; first glume clasping, two thirds to three fourths the length of the spikelet, acuminate, 7-9-nerved, the midnerve usually scabrous toward the apex; second glume slightly longer than the sterile lemma, both much exceeding the fruit, 9-nerved, the midnerves scabrous toward the apex; fruit 3.5 mm. long, about 1.5 mm. wide, narrowly ovate.
Type? locality: Probably South Carolina.
Distribution: Sandy seashore, Connecticut to Georgia; Mississippi.

Panicum amarulum Hitchc. & Chase, Contr. U. S. Nat. Herb. 15:
96. 1910.
Plants glaucous, but less so than in P. amarum, glabrous throughout, cespitose in large bunches sometimes as much as a meter across, 1-2 meters high; culms simple above the base, stout, sometimes 1 cm. thick; leaf-sheaths mostly overlapping; ligule dense, about 3 mm. long; blades erect or ascending, 20-50 cm. long, 5-12 mm. wide, broadest at the base, more or less involute, pilose at the base on the upper surface; panicles finally exserted, one third the height of the plant or more, 5-10 cm. wide, slightly nodding, compact, densely flowered, the long, fascicled branches erect but more or less spreading at their tips, spikelet-bearing from the base ; spikelets short-pediceled, 4.3-5.5 mm. long, 1.7-2 mm. wide, narrowly ovate, acuminate, strongly nerved; first glume half to two thirds as long as the spikelet, acuminate, 5-7-nerved; second glume slightly longer than the sterile lemma, both 7-9-nerved, pointed beyond the fruit; fruit 3-3.5 mm. long, about 1.4 mm. wide, narrowly ovate, bluntly pointed.
Type locality: Virginia Beach, Virginia.
Distribution: Sandy sea shores, Virginia to Florida; Bahamas; Cuba.